Curling head



Jan. 3, 1961 E. DE GEAR 2,966,871

' CURLING HEAD Filed May 28, 1957 4 Sheets-Sheet 1 FIG.|

INVENTOR. EDWARD DeGEAR AT TORNEYS Jan. 3, 1961 E. DE GEAR 2,966,871

CURLING HEAD Filed May 28, 1957 4 Sheets-Sheet 2 IN VEN TOR.

EDWARD DeGEAR Jan. 3, 1961 E. DE GEA 2,966,871

CURLING HEAD Filed May 28, 1957 4 Sheets-Sheet 3 FIG-.5 I

lllh D %f 1 W um W 44 I 4H 2 4 IN V EN TOR.

EDWARD DeGEAR ATTORNEYS Jan. 3, 1961 E. DE GEAR 2,966,871

CURLING HEAD Filed May 28, 1957 4 Sheets-Sheet 4 INVENTOR- EDWARD DeGEAR WM ATTORNEYS United States Patent CURLING HEAD Edward De Gear, San Francisco, Calif., assignor to American Can Company, New York, N.Y., a corporation of New Jersey Filed May 28, 1957, Ser. No. 662,081

Claims. (Cl. 11324) The present invention relates to a curling head for curling the flanges of noncircular can ends to facilitate uniting of the ends to can bodies to produce cans or containers and has particular reference to an improved curling head having a novel rocker type curling unit.

An object of the instant invention is to provide a curling head which is compact and simple in construction but yet of sufficient ruggedness to withstand the excessive curling pressures required to curl sheet metal can ends at high speed rates of production.

Another object is to provide such a curling head with unitary curling devices enclosed in a rockable housing so as to combine all of the oscillatory movable parts in a single unit for compactness and efl'iciency of operation.

Another object is to provide for the quick and easy removal of the curling units without disturbing other adjacent elements of the curling head so that adjustments and repairs may be made without complete or even partial, disassembly of the head.

Another object is to provide for a single pressure element in each curling unit so that the one pressure element furnishes all of the pressure requirements of the unit and is combined in the unit for removal therewith.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

Figure l is a vertical sectional view of a curling head embodying the instant invention, with parts broken away;

Fig. 2 is a fragmentary sectional view of certain of the parts disclosed at the left in Fig. 1, with the parts shown in a different position;

Figs. 3 and 4 are sectional plan views taken substantially along the lines 3-3, 4-4, respectively in Fig. 1;

Fig. 5 is a sectional plan view taken substantially along the broken line 5-5 in Fig. 1;

Fig. 6 is a fragmentary schematic sectional plan view combining parts shown in Figs. 4 and 5 and showing their cooperation during the cycle of operation of the head; and

Fig. 7 is a schematic perspective view of certain related parts of the head, with parts broken away and parts shown in section.

As a preferred and exemplary embodiment of the instant invention, the drawings illustrate a high speed rotary type curling head for curling the outer peripheral edge portions of noncircular sheet metal can ends A (Fig. l) to facilitate subsequent attachment or uniting of the can ends to cans or can bodiesby an interfolding of their flange parts in the usual manner to produce conventional end seams. By way of example the drawings show a curling head designed to curl countersunk panel, rectangu lar can ends having rounded corners and a surrounding substantially flat flange B. The curling operation bends inwardly the outer peripheral edge portion of the flange B to produce a curl C (Fig. 1).

During the curling operation, the can end A with its flange B projecting out into the open in an exposed position, is held clamped between a stationary chuck 21 pro vided as a part of the curling head and a lifter pad 22 which preferably is moved toward and away from the chuck as in conventional can end curling machines. The chuck 21 preferably fits into the countersunk panel section of the can end A and for this purpose the contour of the chuck preferably is the same shape as the'can end.

As is usual in conventional curling machines, the curling head chuck 21 is formed on or is secured to the lower end of a chuck sleeve 24 (see also Figs. 3 and 7) which extends up through the middle of the curling head and at its upper end is secured in a stationary position in any suitable manner in the frame of the machine, such as is shown in United States Patent 2,502,413, issued April 4, 1950, to S. Birkland on Seaming Head for Containers. The curling head rotates around this chuck sleeve.

Usually a knockout pad 25 (Fig. 4) is provided in the chuck 21 to eject the curled can end from the chuck when the lifter pad 22 moves down at the termination of ahave grooved curl-forming outer peripheries aligned with the flange B of a can end A held against the chuck 21 These curling rollers 31 are mounted in the curling head for rotation around the stationary can end in an orbit parallel to the contour of the end and the chuck therein. During this travel the rollers are also moved toward and away from the chuck to contact the can end flange and bend it into the curl C and then towithdraw from the can end so that the latter may be discharged from the chuck.

The curling rollers 31 are oscillatably mounted in curling units D (Fig. 2) which in themselves are oscillatably mounted in the curling head. There are two of these units disposed diametrically opposite in the head so that the curling rollers 31 operate against opposed points on the flange of the can end. The curling units D are mounted in a substantially cylindrical, hollow head body 33 (Figs. 1 and 5) having a hub 34 keyed to a driving sleeve 35 surrounding the chuck sleeve 24. Thedriving sleeve 35 extends up above the head body 33 and is formed with a gear 36 which meshes with and is driven by a gear 37 which is a part of the conventional curling machine. The gear 37 and hence the gear 36 and the head body 33 connected thereto is rotated continuously in any suitable manner.

Each curling unit D is mounted in the rotatable head body 33 in such a manner that it can be readily removed without disturbing any of the other parts of the head so that the units may be replaced, repaired or adjusted for different sizes of can ends or for other reasons. For this purpose each unit D comprises an oscillatable vertically disposed cylindrical hollow housing 40 (Figs. 1 and 7) having a pair of laterally extending, oppositely disposed trunnions 41 located intermediate the ends of the housing. The trunnions 41 are carried in half-bearing blocks 42 formed on the head body hub 34. Half-bearing caps 43 formed as part of a cover 44 (Fig.

5) disposed in a recess 45 in the head body 33 retain.

remove the roller from the flange at the termination of the curling operation;

Oscillation of the housing 40 is effected through a cam roller 47 (Figs. 1, 2, 3, 5, 6' and 7) carried on lugs 48 which project out from the housing adjacent the upper end thereof. This cam roller 47 engages against an edge cam 49 which freely surrounds and is rotatable on the driving sleeve 35. The cam 49 is formed on an upright hub 51 having edge driving serrations 52 which mesh with similar driving serrations in a cam rotating sleeve 54 freely mounted on the driving sleeve 35. At its upper end the cam rotating sleeve 54 is formed with a gear 55 which meshes with and is driven by a continuously rotating gear 56 which is a part of the conventional curling machine and is driven in any suitable manner. The gear 56 is driven in unison with the gear 37 and is slightly less in diameter than the gear 37 for rotating the gear 55 slightly slower than the gear 36. This is a conventional differential gear arrangement which is common in curling heads used in the can making industry.

Retaining of the curling rollers 31 in their non-circular orbit parallel with the contour of the can end A as they travel around the can end and the chuck 21, is effected by cam action. For this purpose, the curling roller 31 of each curling unit D is mounted on the outer end of a roller arm 61 (Figs. 1, 2, 4, 6 and 7) the opposite end of which is attached to a vertical shaft 62 which extends up through the housing 40 and is carried in bearings 63 formed in the opposite ends of the housing. Above the housing the shaft 62 carries a cam arm 65 which preferably projects'in substantially the same direction as the roller arm 61 and which at itsouterend carries a camv roller 66 which engages against a stationary internal or ring cam 67., The cam'67 surrounds thecam sleeve S4 at a level just above the rotatable head body 33 and is clamped againstrdtationin a frame part 68 (Fig 1) Of the curling machine frame.

In order to maintain the cam rollers 47, 66 in contact with their respective cams 49, 67, a single pressure element in the form. of a coiled spring 69 (Figs. 1, and 7) is provided. This spring 69 preferably surrounds the vertical shaft 62. The spring is formed in two connected sections so that at its mid-point it is secured by a screw 70 to the vertical shaft 62 and at its ends are formed hooks that are engaged over an edge 71 of the housing 40. The single spring 69 thus exerts a tor.- sronal stress or pressure against the revoluble shaft 62 to hold the' cam roller 66 engaged against the ring cam 67 and at the same time said spring exerts a pressure against the housing 40 to urge its cam roller 4-7 toward the rotatable edge cam 49 to maintain contact between these two latter parts.

With such a construction of curling head, the curling roll mechanism is entirely mounted in and on the housmg 40 to carry the curling roll 31 around its orbit parallel With the contour of the can end to be curled and th e entire housing 40 is rocked on its trunnions 41 by cams and roller elements 49, 47 to shift the curling rollers 31 into and out of engagement with the can end flange B to perform the curling operation which results in the curl C.

It is thought that the invention and many of its attendant advantages will be understood from the forego- 1ng description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof. i

I claim:

1. A curling head for curling flanges of non-circular can ends to facilitate uniting of the ends to can bodies, comprising a chuck for holding a can end to be curled, said chuck having a contour corresponding to the shape of the can end, a head body having rotative movement around said chuck, means for rotating said head body, a vertically disposed housing having laterally projecting trunnions intermediate its ends journaled in said head body for tiltable oscillation of said housing relative to said body, a vertically disposed tiltable and oscillatable shaft journaled in said housing, said shaft on one side of said trunnions having an arm carrying a curling roller aligned with said chuck and on the opposite side of said trunnions having an arm carrying a cam roller, a stationary follower cam engageable with said cam roller for rotatably oscillating said shaft during rotation of said head body to guide said curling roller around said chuck in an orbit parallel to the contour of the chuck, cam means for tiltably rocking said housing on its said trunnions during rotation of said head body to modify the said orbit movement of saidcurling roller to shift said curling roller into and out of curling position relative to said chuck, and a torsion spring surrounding and intermediately secured to said shaft, the free ends of said spring engaging said housing so as to tend to axially rotate said shaft for holding said cam roller in engagement with said stationary follower cam and for holding said cam means in operative engagement for the respective purposes specified.

2. A curling head as defined in claim 1, wherein said cam means for tiltably rocking said housing comprise a cam roller rotatably mounted in said housing and held by said torsion spring in engagement with a central rotatable edge cam within said head body.

3. A curling head for curling flanges of non-curicular can ends to facilitate uniting of the ends to can bodies, comprising a chuck for holding a can end to be curled, said chuck having a contour corresponding to the shape of. the can end, a hollow head body having rotative movement around said chuck, means for rotating said head body, a vertically disposed housing having laterally projecting trunnions intermediate its ends journaled within said head body for tiltable oscillation of said housing relative to said body, a vertically disposed tiltable shaft rotatably journaled in said housing, said shaft on one side of said trunnions having an arm carrying a curling roller aligned with said chuck and on the opposite side of said trunnions having an arm carrying a cam roller, a stationary follower cam engageable with said cam roller for rotatably oscillating said shaft during rotation of said head body to guide said curling roller around said chuck in an orbit parallel to'the contour of the chuck, and means engaging said hous ing and rotatable with said head body for tiltably oscillating said housing on said trunnions and with said shaft to modify the orbit movement of said curling roller to shift said curling roller into and out of curling position relative to said chuck.

4. A curling head as defined in claim 3, wherein a pair of said shafts are journaled in a pair of tiltable housings carried by and bodily revoluble with said head body, and a single central edge cam is rotatable with said head body rotating means for tiltably oscillating said housings during rotation of said head body.

5. A curling head 'as defined in claim 3 having demountable journal means for said trunnions permitting removal of said housing and said shaft as a unit from said rotatable head body without disturbing the remaining elements of the curling head.

References Cited in the file of this patent UNITED STATES PATENTS 

